Apparatus for stressing strand materials



APPARATUS FOR STRESSING STRAND MATERIALS Frank Honig, Edgewood, RI.

@riginal application June 25, 1952, Serial No. 295,439,

now Patent No. 2,738,144, dated March 13, 1956. Digdoetszand this application March 5, 1953, Serial No.

8 Claims. (Cl. 28-71.3)

This invention relates to novel apparatus used in the preparation of textile packages in which the wound strand may consist of one or a plurality of filaments and in which the package may be of self-sustaining type wound on a headless core. The strand which forms such a package may consist of staple fibers or of synthetic tow or other continuous filaments and may be supplied to the winding means, twisted or untwisted, from a previously wound supply package, or, when used in a continuous process, directly from the delivery end of a filament-forming apparatus. l

Prior art apparatus useful in stressing a twisted strand, either for winding a package, for elongating the filaments comprising the strand, or for attenuating the filaments comprising the strand to Vprovide molecular orientation within the filaments, tended to abrade the strand filaments, to strip somelaments from the strand,'or to backup the strand twist toward the package from which the strand was supplied. Back-up of a strand twist could be reduced by protective sizing or agglutination of the strand filaments, but this protective material later had `to be re -V moved and the process as a whole was therefore expensive.

One of the objects of the present invention is to provide means for use in winding a self-sustaining package from strand material such as above described, thereby to insure that each individual constituent filament ofthe tow or strand, whether or not the strand is comprised of twisted filaments, no matter what particular position such filament may occupy in a given convolution in a` wound package, will be wound withla degree of tension such that each individual filament will effectively contribute to resist the bursting action of centrifugal force when the wound package is rotated at high speed.

Another object is to provide for the attenuating `or winding, or both, of a strand comprising hunched or twisted filaments, staple fibers, or both, at any stress from zero (practically speaking) to a stress just below the breaking point of said strand, Without requiring sizing or agglutinization of the strand, while maintaining the initial, substantially uniform twist throughout the entire length of said strand, that is, withoutbacking up the twist in the strand towards the supply package, which, otherwise, would cause localized twist gradient or twist variation in sections of the strand.

Another,` object is to provide a resilient, positive, rolling gripping po-int fo-r` the strand or tow, and to locate said point in a neutral position with respect to the fluctuating longitudinal stresses in said strand `or tow, so that it will always maintain a positive gripping action independently of any stress variation inherent in the strand or tow being operated on, that is to say, to provide a constantly shifting, positively gripping pinch zone capable of holding a filament or strand with any force from practically zero to the breaking point of the filament or strand without in any way damaging, as by abrasion, distortion, Yor otherwise, a continuous filament, and without removing any of the bers from a strand comprising nited States Patent staple fibers as by stripping, for example: in other words, a positive pinch zone which is neutral in its action.

A further object is to provide for the winding of a self-supporting package on a tubular core, without head or flanges, in such a way that said package may be mounted on and rotated by a spindle at a rotative speed equivalent to a centrifugal disrupting force produced by a peripheral speed of from say 150 to 400 miles per hour, more or less, on the outside periphery of the yarn package, without exploding said package.

Another object is to provide apparatus for tensioning yam to be mercerized without backing up twist in the yarn towards the supply package and without stripping filaments or fibers from the yarn.

The novel apparatusin accordance with the invention and for use in attaining the above objects, comprises a set of strand controlling rolls adapted to receive a strand therebetween at low and sometimes valuable stresses and to deliver the strand therefrom at higher and more uniform stress, and means which can be adjustably set, for determining the amount of stress in the delivered strand. The apparatus is preferably utilized where the operation is primarily of a winding or rewinding nature, in` situations where a filament, tow, strand or yarn is Wound up into a package at the takeup end of continuous yarnspinning apparatus or where it is rewound from one type of package to another type of package as desired in processing such filament, tow, yarn or strand, and Where the stresses to be exerted on the strands or filaments are relatively low. For example, the single set of rolls is useful when a comparatively small percentage of linear attenuation of some or all of theconstituent filaments of a strand is desired either to equalize any length variation in the individual filaments of which the strand is comprised or to stress all filaments of a strand having filaments normally of equal length for winding the strand on a circular core;,when it is desired to; discharge or withdraw the strand at a uniform and predetermined higher stress than that at which it is received, and simultaneously to maintain substantially uniform twist throughout the entire l length of the strand, Withou backing up the twist towards the supply end of the strand being operated on; or when it is desired to prevent waste formation of staple fiber yarns'or damage, as by abrasion for example, to continuous filaments.

Other objects, advantages and details of construction will be more fully described by reference to the accompanying drawings in which:

Fig. l is amore or less diagrammatic front elevation, showing an embodiment of the invention in which a single pair of rolls is used, the apparatus being illustrated asin use for a rewinding operation suitable for the preparation of a package, subsequently for use to be mounted on a high speed twisting spindle or similar apparatus;

Fig. 3 is a diagram illustrative of a "situation in which the present invention is of'particular utility.

Referring to the drawings, Fig. 3 diagrammatically illustrates a condition which commonly occurs in the preparation of synthetic filament tow. Three spinnerets E are shown asextruding the filaments J, N and L, respectively, which .pass between the rolls, R1 and R? and are then wound on the winding spindle K to form the package W. Among the three filaments illustrated, the one designated I is taut between the spinneret and its point of contact with the roll R1, and in consequence this filament is wound under constant tension into the packagev W. Filament N isV not taut between the spinneret andfthe'roll R1, while the filament L is still more slack.A Consequentljgthe filaments N and L, as wound into the package'V W, are not under the same tension as the filament I and if, at some later time, the package W is rotated at high speed only the filament I is effective to resist centrifugal bursting forces. The apparatus provided by this invention is designed to change the length of the filaments comprising such bunch so that, while the bunch is wound in convoluted form on a core, each filament will be tensioned to effectively contribute to resisting the bursting action of centrifugal force when the wound package is subsequently rotated'at high speed. When all of the lilaments are thus wound under substantially the same tension, they all effectively and concomitantly resist centrifugal bursting force so that the package is able to withstand high speed rotation without disintegrating.

Referring to Fig. 1, the convolute tension equalizing unit Q is shown as comprising a yarn-receiving roll and a yarn-discharging roll 11. Roll 10 is provided with a resilient, yarn-contacting covering or tire 12 (Fig. 2), preferably made of some natural or synthetic rubber compound, cork or similar material, and which is fixed to the roll 10 by any conventional means.

The roll 11 is usually made of hardened steel or some equivalent material, and may be chromium plated on its periphery to preventcorrosion which would damage the delicate filaments coming in contact therewith. Roll 11 is rotatably mounted on a double-row, anti-friction bearing 13 (Fig. 2) which has its inner stud 14 press-iitted into one arm 15 of a balance scale beam 15a.

The roll 10 is rotatably rounted on a double-row, antifriction bearing 16 (Fig. 2) with its inner stud 17 pressfitted into an eccentric 18. The eccentric 18 is rotatable in the arm 19 of balance scale beam 15a. The arrangement is such that by rotating the eccentric 18 the axis of the roll 10 may be moved toward or from that of roll 11 so that the resilient tire 12 of roll 10 may be pressed into pinching relation with the periphery of roll 10 to provide a pinch or nip point P (Fig. l) for the yarn Y.

The balance scale beam 15a is freely pivoted on a stationary stud 20 riveted at its forward end into a rigid housing 21 (Fig. 2). A screw 22, having threaded engagement with an axial bore in the rear end of stud 20, serves to fasten a cupped back cover plate 23 to the housing 21. The axes of the rolls 10 and 11 are in the same plane with the axis of stud 20 so that the pinch point P is in a neutral position with respect to any movement or lack of movement of the scale beam 15a. Variation in pinching pressure between the rolls or variation in stresses in the yarn Y, as it passes through this point, will have no effect on the movement or lack of movement of the scale beam 15a.

The rolls 10 and 11V have elongate hub portions 10a' and 11a, respectively, which pass freely through horizontally elongate slots in the housing 21.

An arm 24 (Figs. l and 2) is pivoted on stud 20 at a point between the scale beam 15a and the housing 21. The free lower end of arm 24 is provided with a friction brake lining 25 (Fig. l) which may bear against the periphery of hub 11a of roll 11, being urged toward said hub by a compression spring 26 whose lower end is supported on a fixed lug 27 projecting from the housing 21.

Compression spring 26 has a limited amount of extension so that it will follow the swinging movement of scale beam 15a with decreasing, resilient pressure of the brake lining against the hub 11a (up to the end of its limited movement) when the movement of said beam is clockwise. Beyond' that point the hub 11a will no longer contact the brake lining of the arm 24. When the motion of the beam 15a is counterclockwise, the arm 24 will follow such motion with increasing resilient pressure of the brake lining against the hub 11a of roll 11. Of course any other conventional means for applying the retarding or braking action on theY roll may be used,` in lieu of the spring and brake lining just mentioned.

' The balance beam 15a is provided with a lug 28 near its central portion (Fig. 1) into which is fastened a spring 29 of tiat steel. The other end 29 of spring 29 projects through an opening (not shown) in the rim of the cover 23 and serves as an indicator of the pressure or load on the scale beam 15a. Indicator scale graduations are formed on a part of cover 23, as indicated at 30. An adjusting thumb screw 31 is provided for applying any desired load within the capacity of the particular ernbodiment to the scale beam 15a, and (by reason of the retarding action of the brake lining) to the strand material passing between the rolls 10 and 11.

The housing 21 is provided with an integral lug 32 (Fig. l) which supports a freely rotating, grooved idler roll 33 adapted to guide the yarn Y away from the mechanism.

A freely rotating yarn-guiding, grooved idler roll 34 (Fig. l), carried by a conventional reciprocating distributor arm (not shown) of a Winder, serves to distribute the yarn Y as it is being wound on a headless core 36 to form the desired type and size of yarn packaged indicated at 37. The supply package is indicated at 38 and it may be a cone, as shown, or any other form of supply package desirable or convenient. Any other suitable supply may be employed. For example, the yarn may be received directly from the filament-forming apparatus.

As illustrated, the yarn is taken from a non-rotating package over-end through a" conventional guide 39 fast to housing 21. This imparts a slight twist, one twist for each convolution taken from package 38. The yarn wraps the roll 10 with about one-half a turn, then passes between the rolls at the pinch point P, and then wraps roll 11 with about one-half a turn. It then passes up over the grooved guide idler 33 and distributing idler 34 and is wound up on core 36 which is driven by any conventional winding machine mechanism (not shown). To permit rapid threading of the device, the rolls 10 and 11 are provided with rounded taper front ends, as indicated at 10h and 11b (Fig. 2).

In operation the pinch point P (Fig. l) is at a neutral or zero point, that is to say, at the fulcrum of the beam 15%. InV effect, ,the tangent points of the yarn with rolls 10 and 11, indicated at 10c and 11, define the leverage length of the scale beam 15 through which the stresses are balanced by the yarn being operated on.

By this arrangement a gradually increasing or decreasing retarding force is applied by the rolls 11 and 10. The change in the retarding force is very smooth and gradual and yet so Vsensitive in response to rapid stress surges that winding speeds well above 3,000 feet per minute may be employed. Very satisfactory packages may be made with as high as 10,000 feet per minute winding velocity when winding certain strand materials.

vFor example, assuming that the desired loading stress has been set by the screw 31, the delivery portion Ya of the yarn will be pulled through the device under that stress. Should there be, for some reason, an increase in the stress at Ya it Vwill lift up or rock the roll assembly about pivot 20 clockwise and thus reduce the normal retarding force of the friction brake lining 25.

On the other hand, should there be a stress increase (resistance to travel) vin the incoming yarn end Yb, this part of the yarn will likewise rock the roll assembly clockwise about pivot 20 and reduce the normal retarding force of the friction brake lining 25. Thus, stress uniformity may be controlled by either or both the incoming or outgoing portions of the strand material, independentlyof one another or jointly, as the case may be.

Since the yarn is held byV the pinching action of the rollers in a rolling contact (as contrasted with a frictional pressure), located in a neutral position, any twist initial in the yarn will remain undisturbed, that is to say, it will not be backedvup-towards the supply package 38, as happens when a twisted strand is passed between frictional retarding elements,r or an element with 360 or more degrees of wrapping thereon; thus, the initial distribution of twist is maintained in the yarn of wound package 37.

In the arrangement shown in Figs. 1 and 2, the operating power is transmitted vfrom the driven `c'e 36* through the yarn end Ya. This arrangement is, in general, used when the attenuation of the filament isto take place for temporary circumferential length equalization purposes, or when the total attenuation is held to a low point, say about 1% to 5%, more or less, depending on the size and on the particular material which is to be equalized.

When using this arrangement, the yarn being discharged is always under some stress, depending on the adjustment. It is thus particularly advantageous for use in re-winding the yarn from one form of package to another form of package where some stress in the package is desirable, such, for example, as when the package is to be used in subsequent twisting operations at very high speeds, or for the mercerization of cotton yarn.

This application is a division of my copending application Serial No. 295,439, led June 25, 1952, now U.S. Patent #2,738,144.

While certain desirable embodiments have herein ybeen illustrated and described, it is to be understood that the invention may have various embodiments without` departing from the spirit and scope of the invention as set forth in the appended claims.

I claim:

1. In apparatus of the. class described wherein yarn from a supply passes between tworolls which turn about parallel axes on its way to a power-driven winding device, the rolls being mounted on the opposite arms, respectively, of a scale beam, means guiding the yarn from the supply so that it first contacts one roll at a point which is in a plane passing through the axes of the two rolls, means guiding the yarn to leave the other roll at a point which is in the aforesaid plane, a brake for retarding the rotation of the latter roll, a spring arm iixed to the scale beam, and adjustable means for applying force to said spring arm thereby to rock the scale beam in a direction to cause the brake to apply a predetermined normal retarding force, the parts being so constructed and arranged that abnormal tension in the yarn which leads from the supply or in the yarn which leads to the winding device creates force tending to swing the scale beam oppositely to the direction in which it is urged by said spring arm.

2. In combination in apparatus of the class described wherein yarn from a supply mass passes between two rolls which turn about parallel axes, a bearing for each roll, a centrally fulcrumed scale beam supporting said bearings at opposite sides of and at substantially equal distances from the fulcrum, a brake for retarding rotation of one of said rolls, means urging the scale beam in a direction to create pressure between the brake and the roll with which it cooperates, and means for guiding yarn from the supply mass in a direction to approach and tangentially to` contact one of said rolls at a point adjacent to one end of the scale beam and to leave the other roll at a tangent point adjacent to the other end of the scale beam, the force exerted by the strand in leaving the latter roll being so directed as to tend to swing the scale beam in a direction to reduce the brake pressure.

3. In combination in apparatus wherein strand from a supply is wound upon a rotating core, a pair of rolls turning about parallel axes, the strand passing between the rolls on its Way from the supply to the core, the axes of the rolls being so spaced apart that the yarn is pinched in passing between the peripheral surfaces of the rolls, means, comprising a member mounted to rock about a xed axis parallel to the axes of the rolls, for supporting said rolls for bodily, concomitant equal motion in opposite directions, means guiding the yarn from the supply into contact with one roll at a point such that the resistance to withdrawal of the yarn from the supply creates a force tending to move the last-named roll bodily in one direction, means guiding the yarn to leave the other roll at a point such that the tension exerted by the rotating core creates a force tending to move the second roll bodily in a direction opposite tov that in 'which the rst roll tends to move, means for adjustably opposing such bodily motion of the rolls, brake means comprising a surface coaxial with one of said rolls and spaced from the yarn-4 contacting surface of said roll, and a movable brakeshoe co-operable with said brake surface and whose position, with respect to said brake surface, varies in accordance with the position of the member which supports the rolls.

4. Apparatus, according to claimV 3, further characterized in that the support for the two rolls is a centrally fulcrumed scale beam having the rollers mounted adjacent to its opposite ends and at equal distances from its fulcrum.

comprisinga centrally ulcrumed scale beam for support- Ving said rolls for bodily, concomitant equal motion in opposite directions, means guiding the strand from the supply into contact with one roll ata-point such that the resistance to withdrawal of- ,the strand from the supply creates a force'tending to move the last-named roll bodily in one direction, meansguiding the strand to leave the other roll at a point such that the tension exerted by the rotating core creates aforce tending to move the second roll bodily in 'a direction opposite toV that in which the rst roll tends to move, spring means for adjustably opposing such bodily motions of the roll, and bearings for the respective rolls arranged at opposite ends of the centrally fulcrumed scale beam, said spring means opposing tipping of the scale beam in response to the force exerted by the strand.

6. In combination in apparatus wherein yarn from a supply is wound upo'n a rotating core, a pair Vof rolls turning about parallel axes, the yarn passing between the rolls on its way from the supply to the core,v means comprising a centrally fulcrumed scale beam for supporting the rolls for bodily, concomitant equal motion in opposite directions, means guiding the yarn from the supply into contact with one roll at a point such that the resistance to Withdrawal of the yarn from the supply creates a force tending to move the last-named roll bodily in one direction, means guiding the yarn to leave the other roll at a point such that the tension exerted by the rotating core creates a force tending to move the second roll bodily in a direction opposite to that in which the first ro'll tends to move, means for adjustably opposing the bodily motion of the rolls, bearings for the respective rolls which are mounted on opposite arms of the centrally fulcrumed scale beam, and means for bodily adjusting one of said bearings toward the other, thereby to' vary the distance between the rolls.

7. In combination in apparatus wherein strand from a supply is wound upon a rotating core, a pair of rolls turning about parallel axes, the strand passing between the rolls on its Way from the supply to' the core, means for supporting said rolls for bodily, concomitant equa motion in opposite directions, means guiding the strand from the supply into contact withone roll at a point such that the resistance to withdrawal of the strand from the supply creates a force tending to move the last-named roll bodily in one direction, means guiding the strand.

to leave the other roll at a point such that the tensioncreated by the rotating core creates a force tending to move the second roll bodily in a direction opposite to that in which the yiirst roll tends to move, means for adjustably opposing such bodily motion of the rolls, the roll from which the yarn is delivered to the winding core having a hub, a brake-shoe for applying frictional pressure to the hub, and a spring which urges the brake-shoetoward the hub, the parts being so constructed and arranged that the roll which has the hub is movable bodilyaway from the brake-shoe in response to abnormal tension exerted by the yarn leading to the winding core..

8. In combination in apparatus wherein yarn from a supply is., wound npon 'a rotating core, a pair of rolls turning about parallel axes, the yarn passing between the rolls on its way from the supply to the core, means cornprising a scale beamv for supporting said rolls for bodily, concomitant eqnal motion in opposite directions, means guiding the yarn from the supply into contact with one roll at a point snch that the resistance` to withdrawal of the yarn from the supply creates a force tending to move the last-named roll bodily in one direction, means guiding the yarn to leave the other roll at a point such that the tension exerted by the rotating core creates a force tending to move the second roll bodily in a direction opposite to that in which the firstV roll tends to move, spring means for adjustably opposing such bodily motion of the rolls, the rolls being mounted at opposite ends of thel scale beam, the roll from which the yarn is delivered to the winding core having a hub, a pivoted arm carrying a brake-shoe for applying retarcling pressure to the hub, and a spring which normally urges said arm in a direction to Contact the brake-shoe with the hub, said spring having a limited range of action so that the hub may, at times, move completely out of contact with the brakeshoe, said lirst spring means urging the scale beam in a direction to move the hub toward the brake-shoe, the parts being so constructed and arranged that abnormal resistance to withdrawal of the yarn from the supply Swings. the beam in. opposition to said first. spring means.

References Cited in the tile of this `patent UNITED STATESV PATENTS 1,595,818 Bliss Aug. 10, 1926 1,935,931 Baumert et al. Nov. 21, 1933 2,104,809 ODowd Jan. 11, 19,38 2,123,936 Dreyfus July 19, 1938 2.208,497 Coleshill et al. July 16, 1940 2,235,889 Keight Mar.v 25, 1941 2,289,232 Babcock July 7, 1942 2,304,206 Reichel Dec. 8, 1942 2,328,322 Berthold Aug. 31, 1 943 2,359,170 Symmes Sept. 26, 1944 2,362,920 Moore -v Nov. 14, 1944 2,413,073 Saum Dec. 24, 1946 2,486,349 Welch -2-- Oct. 25, 1949 2,538,932 Campbell Jan. 23, 1951 2,581,922 Spencer Jan. 8, 1952 2,628,405 Wentz Feb. 17, 1953 2,667,313 Klein Jan. 26, 1954 2,686,018 Courtney i.- Aug. l0, 1954 2,771,635 Munch Nov. 27, 1956 FOREIGN PATENTS 59,355 Netherlands May 16, 1947 

